We pass in the following chapter to the momentous discovery of Herbert Spencer that the great truth seen by Malthus was not a whole but a half-truth, and that there is a compensating principle, which is at once a source of inspiration and of difficulty to the eugenist. It is in general the principle that as life ascends it becomes less prolific, and its consequences are infinitely more vast than the phrase at first suggests. Had this principle been discovered by a Continental thinker or by a member of a British University instead of by a man who never passed an examination, it would not now need the discussion which we shall have to give it.
[CHAPTER VI]
THE GROWTH OF INDIVIDUALITY
The laws of multiplication.—Implicit or explicit approval of a falling birth-rate involves opposition to the opinion of the man in the street, the general opinion of the medical profession,[23] the bench of bishops and the social prophet and publicist in general. Nevertheless a fall in the birth-rate is a factor in organic progress, and, in general, the level of any species is in inverse proportion to its birth-rate, from bacteria to the most civilised classes of men in the most civilised countries of to-day. But in truth the uninformed opinion, totally contrary to the whole history of life and to the most obvious comparative facts of the birth-rate amongst and within present day human societies, was utterly disposed of forty years ago in the closing chapter of the greatest contribution yet made to philosophic biology—Herbert Spencer's Principles of Biology. The last chapter of that masterpiece is entitled “The Laws of Multiplication.” Unfortunately it has not been read by one in ten thousand of those who think themselves entitled to hold, and even to express, opinions about the birth-rate. Spencer's discovery is the complementary half-truth to the discovery of Malthus, and just as the law of Malthus is pessimistic, so the law of Spencer is optimistic. In a word, Malthus assumed—indeed, formally declared—that there was no natural factor of an internal kind tending to limit the rate of vital fertility. Spencer discovered that there is such a factor, which can and does limit and has been limiting vegetable, animal, and human fertility since the dawn of life.
All reproduction involves an expenditure of energy in some degree on the part of the parent. Now the energy available by any individual is finite. If he expends it all upon reproduction, he himself, or she herself, must cease to exist. This happens in all the lowest forms of life, which multiply by fission or simple splitting. The young bacteria are their sub-divided parent. At the other extreme is the case of the individual who retains the whole of his energy for his own development and life, and has no offspring at all. Such consummate bachelor philosophers as Kant and Spencer may be quoted, and the list of childless men of genius might be extended quite indefinitely. This is not to declare this last state to be the ideal, but merely to point out the logical extremes.
Spencer's principle is that there is an “Antagonism,” or, as we may rather say, an inverse ratio, between “Individuation” and “Genesis”—between the proportion of energy expended upon the individual and the proportion expended upon the continuance of the race. Thus “Individuation,” meaning all those processes which maintain and expand the life of the individual, and “Genesis,” meaning all those processes which involve the formation of new individuals—are necessarily antagonistic. Every higher degree of individual evolution is followed by a lower degree of race multiplication, and vice versâ. Increase in bulk (cf. the elephant), complexity or activity involves diminution in fertility, and vice versâ. This is an obvious à priori principle.
Should the reader declare that there must be something the matter with an asserted principle of progress which leads in theory or in practice to the production of a childless generation, and therefore the end of all progress, and that this principle suggests that the most completely developed man and woman cannot be parents—then I would join in the chorus of fathers and mothers generally, who would say that, in human parenthood, if not, indeed, in sub-human parenthood, the antagonism is reconciled in a higher unity; that the best and most complete development of the individual is effected only through parenthood, in due degree—as Spencer, himself childless, formally declared.
It is impossible here to show how complete is the evidence for Spencer's law, both from the side of logical necessity and from the side of observation. In order to indicate the overwhelming character of the evidence, one would have to transcribe the whole of his long chapter, and to add to it all our modern knowledge of human birth-rates. This cannot be done, but even without it we may venture to say that people who regard a falling birth-rate as in itself, and obviously, a sign of racial degeneration or immorality, or approaching weakness or failure of any kind, can have made no substantial additions to their knowledge of the subject since they themselves formed items in the birth-rate.
Spencer goes on to show, with profound insight, that, in general, greater individuality, or, to put it in other words, the more highly evolved organism, “though less fertile absolutely, is the more fertile relatively.” The supreme instance of this truth is, of course, the case of man, in whom individuation has reached its unprecedented height, who is absolutely the least fertile of creatures,[24] and yet who is relatively the most fertile—unique in his actual and persistent multiplication.